Use a Calculator to Give the Value to the Nearest $$\theta = \cos ^ { - 1 } ( 0.8910 )$$

question 96

Multiple Choice

Use a calculator to give the value to the nearest degree.
- $$\theta = \cos ^ { - 1 } ( 0.8910 )$$

• A) \(27 ^ { \circ }\)
• B) \(25 ^ { \circ }\)
• C) \(63 ^ { \circ }\)
• D) \(29 ^ { \circ }\)

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Definitions:

Cell-Mediated Immunity

Cell-mediated immunity is an immune response that does not involve antibodies but rather the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen.

Periarterial Lymphatic Sheath

Dense accumulation of lymphocytes (white pulp) surrounding arteries within the spleen.

Red Pulp

A component of the spleen consisting of blood-filled venous sinuses and splenic cords, involved in the filtration of blood and removal of old or damaged red blood cells.

Spleen

An organ involved in the production and removal of blood cells and part of the immune system.